Who has been buying IBJ, Inc. stock?

10 distinct investors have filed 26 disclosed large-shareholding filings in IBJ, Inc. (6071), most recently on 2026-04-22. Each filer, their role, the number of shares and the price at filing are listed in the table on this page.

How many insider filings does IBJ, Inc. have?

IBJ, Inc. has 26 buy-side and 20 sell-side disclosures on record, covering ¥8.2B ($53.1M) in total reported value, spanning 2021-04-02 to 2026-04-22.

Do insider buys in Japanese stocks predict returns?

Not uniformly. StockDrifts scored 101,000+ Japanese large-shareholding filings on fixed 12-month forward returns and found the predictive power concentrated in specific filer types and filing patterns rather than spread evenly across all disclosures.

IBJ, Inc. 6071

Company

株式会社IBJIBJ, Inc.

Investors

Buys

Total Value

¥8.2B ($53.1M)

Avg Return

-8.27%

Last Filing

2026-04-22

IBJ, Inc. (6071) has 26 disclosed large-shareholding filings and 20 disclosed disposals on record, filed by 10 distinct investors. Together those filings cover ¥8.2B ($53.1M) in reported transaction value. The earliest filing StockDrifts holds for IBJ, Inc. is dated 2021-04-02; the most recent is 2026-04-22. Across these filings the average return since disclosure is -8.27%, measured from each filing date to the latest available close.

Price & insider activity (12 months)

Recent filings

Date	Type	Source	Insider	Purpose	Shares	Price at filing	Return	Value
2026-09-25	BUY	unknown	アイエス株式会社	activist	142.1K	¥912	-	-
2026-09-25	SELL	unknown	石坂茂	activist	10.7M	¥912	+0.0%	¥406M ($2.6M)
2026-09-07	BUY	unknown	アイエス株式会社	unknown	142.1K	¥915	-	-
2026-09-07	SELL	unknown	石坂茂	activist	11.2M	¥915	+0.3%	¥415M ($2.7M)
2026-09-07	BUY	Market Buy	アイエス株式会社	activist	142.1K	¥915	-0.3%	¥19M ($124K)
2026-09-07	SELL	unknown	石坂茂	activist	11.6M	¥915	+0.3%	¥215M ($1.4M)
2026-09-07	SELL	unknown	石坂茂	activist	11.8M	¥915	+0.3%	¥77M ($496K)
2026-09-07	SELL	unknown	石坂茂 Shigeru Ishizaka	activist	11.8M	¥915	+0.3%	¥77M ($496K)
2026-09-07	SELL	unknown	石坂茂 Shigeru Ishizaka	activist	11.6M	¥915	+0.3%	¥215M ($1.4M)
2026-09-07	BUY	Market Buy	アイエス株式会社	unknown	120.0K	¥915	-0.3%	¥111M ($719K)
2026-09-07	SELL	unknown	石坂茂 Shigeru Ishizaka	activist	11.2M	¥915	+0.3%	¥415M ($2.7M)
2026-08-21	BUY	unknown	SMBC日興証券株式会社	other	165.6K	¥955	-4.5%	¥158M ($1.0M)
2026-08-21	BUY	Market Buy	三井住友DSアセットマネジメント株式会社	passive	2.0M	¥955	-4.5%	¥1.9B ($12.3M)
2026-07-23	SELL	unknown	SMBC日興証券株式会社	other	172.8K	¥816	-11.8%	¥425M ($2.7M)
2026-07-23	BUY	Market Buy	三井住友DSアセットマネジメント株式会社	passive	1.7M	¥816	+11.8%	¥82M ($531K)
2026-07-03	SELL	Market Buy	中本哲宏	passive	2.4M	¥814	-12.0%	¥291M ($1.9M)
2026-07-03	BUY	Market Buy	株式会社TNnetwork	passive	3.2M	¥814	-	-
2026-04-22	BUY	Market Buy	三井住友DSアセットマネジメント株式会社	passive	1.6M	¥746	+22.3%	¥1.2B ($7.6M)
2026-04-22	BUY	unknown	SMBC日興証券株式会社	other	694.4K	¥746	+22.3%	¥518M ($3.3M)
2025-12-04	SELL	unknown	三井住友トラスト・アセットマネジメント株式会社	other	338.2K	¥754	-20.9%	¥13M ($82K)
2025-12-04	SELL	unknown	アモーヴァ・アセットマネジメント株式会社	other	1.6M	¥754	-20.9%	¥424M ($2.7M)
2025-09-19	BUY	unknown	三井住友トラスト・アセットマネジメント株式会社 Sumitomo Mitsui Trust Asset Management Co.,Ltd.	other	357.2K	¥859	+6.2%	¥1.4B ($9.3M)
2025-09-19	SELL	unknown	アモーヴァ・アセットマネジメント株式会社 Amova Asset Management Co., Ltd.	other	2.1M	¥859	-6.2%	¥206M ($1.3M)
2025-07-25	SELL	Market Buy	中本哲宏 Nakamoto Tetsuhiro	passive	2.8M	¥832	-9.6%	¥374M ($2.4M)
2025-07-25	BUY	Market Buy	株式会社TNnetwork TNnetwork Co., Ltd.	passive	3.2M	¥832	-	-
2025-07-01	BUY	Market Buy	株式会社TNnetwork TNnetwork Co., Ltd.	passive	3.2M	¥838	-	-
2025-07-01	SELL	Market Buy	中本哲宏 Nakamoto Tetsuhiro	passive	3.2M	¥838	-8.8%	¥355M ($2.3M)
2025-04-18	BUY	Market Buy	石坂茂 Shigeru Ishizaka	activist	11.9M	¥617	+47.8%	¥8M ($50K)
2025-04-18	BUY	unknown	石坂茂 Shigeru Ishizaka	activist	11.9M	¥617	-	¥8M ($50K)
2024-04-15	BUY	Market Buy	石坂茂 Shigeru Ishizaka	activist	11.9M	¥543	+68.0%	¥196M ($1.3M)
2024-04-15	SELL	Market Buy	石坂美江 Mie Ishizaka	activist	0	¥543	-68.0%	¥3.2B ($20.6M)
2024-04-04	BUY	Market Buy	株式会社TNnetwork TNnetwork Co., Ltd.	passive	3.2M	¥531	-	-
2024-04-04	BUY	Market Buy	中本哲宏 Nakamoto Tetsuhiro	passive	3.6M	¥531	-	-
2024-04-04	BUY	Market Buy	中本哲宏 Nakamoto Tetsuhiro	passive	3.6M	¥531	-	-
2024-04-04	BUY	Market Buy	株式会社TNnetwork TNnetwork Co., Ltd.	passive	3.2M	¥531	-	-
2023-07-21	SELL	unknown	三井住友トラスト・アセットマネジメント株式会社 Sumitomo Mitsui Trust Asset Management Co.,Ltd.	other	341.0K	¥676	-34.9%	¥20M ($128K)
2023-07-21	BUY	unknown	日興アセットマネジメント株式会社 Nikko Asset Management Co.,Ltd.	other	2.4M	¥676	+34.9%	¥355M ($2.3M)
2023-06-06	BUY	unknown	三井住友トラスト・アセットマネジメント株式会社 Sumitomo Mitsui Trust Asset Management Co.,Ltd.	other	368.2K	¥673	+35.5%	¥248M ($1.6M)
2023-06-06	BUY	unknown	日興アセットマネジメント株式会社 Nikko Asset Management Co.,Ltd.	other	1.8M	¥673	+35.5%	¥1.2B ($7.9M)
2023-04-14	BUY	Market Buy	石坂茂 Shigeru Ishizaka	activist	11.6M	¥674	+35.3%	¥3M ($18K)
2023-04-14	BUY	Market Buy	石坂美江 Mie Ishizaka	activist	60.0K	¥674	+35.3%	¥3.8B ($24.8M)
2022-11-02	BUY	Market Buy	石坂茂 Shigeru Ishizaka	activist	11.6M	¥943	-3.3%	¥174M ($1.1M)
2022-11-02	BUY	Market Buy	石坂美江 Mie Ishizaka	activist	178.6K	¥943	-	-
2022-10-12	BUY	Market Buy	株式会社TNnetwork TNnetwork Co., Ltd.	passive	3.2M	¥975	-	-
2022-10-12	BUY	Market Buy	中本哲宏 Nakamoto Tetsuhiro	passive	3.6M	¥975	-	-
2022-08-17	SELL	unknown	いちよしアセットマネジメント株式会社 Ichiyoshi Asset Management Co., Ltd.	other	1.8M	¥908	-0.4%	¥473M ($3.1M)
2022-03-04	SELL	unknown	株式会社TNnetwork TNnetwork Co., Ltd.	activist	3.2M	¥729	-25.1%	¥43M ($277K)
2022-03-04	SELL	unknown	中本哲宏 Nakamoto Tetsuhiro	activist	3.6M	¥729	-25.1%	¥265M ($1.7M)
2022-03-04	SELL	unknown	中本哲宏 Nakamoto Tetsuhiro	activist	3.6M	¥729	-25.1%	¥46M ($296K)
2022-03-04	SELL	unknown	中本哲宏 Nakamoto Tetsuhiro	activist	3.6M	¥729	-25.1%	¥265M ($1.7M)

Showing the 50 most recent of 101 filings.

Frequently asked questions

Who has been buying IBJ, Inc. stock?: 10 distinct investors have filed 26 disclosed large-shareholding filings in IBJ, Inc. (6071), most recently on 2026-04-22. Each filer, their role, the number of shares and the price at filing are listed in the table on this page.
How many insider filings does IBJ, Inc. have?: IBJ, Inc. has 26 buy-side and 20 sell-side disclosures on record, covering ¥8.2B ($53.1M) in total reported value, spanning 2021-04-02 to 2026-04-22.
Do insider buys in Japanese stocks predict returns?: Not uniformly. StockDrifts scored 101,000+ Japanese large-shareholding filings on fixed 12-month forward returns and found the predictive power concentrated in specific filer types and filing patterns rather than spread evenly across all disclosures.

More on this data

Every trade listed above comes from an official regulatory disclosure. For how StockDrifts scores these disclosures, see the Japan insider signal tier research, or browse every Japanese stock we track.